May 15 through Sept. 13
Cool off on hot summer days at one of the park's two excellent swimming beaches. Swimming is permitted at Monsanto and Pim lakes only. No cans, glass bottles, coolers, fires, alcohol or pets are allowed at the beaches.
A large shelter with picnic tables is located at Monsanto Lake and is available on a first-come, first-served basis. There are also benches, a volleyball net, a change house and a vault toilet. Pim Lake and beach is smaller than Monsanto, but has benches, picnic tables, barbecue grills, a change house and a vault toilet
The use of metal detectors is allowed on Monsanto and Pim beaches only with written permission from the Division of State Parks. Permits can be obtained free of charge by writing to the Division of State Parks, P.O. Box 176, Jefferson City, Mo. 65102. Permitted use is allowed during daylight hours after Labor Day to Memorial Day, and 7 a.m. to 9 a.m. from Memorial Day through Labor Day. Digging tools must not exceed 12 inches in length and 3 inches in width.
Scuba diving is permitted in Monsanto and Pim lakes. You must be certified and must be accompanied by another certified diver. You are required to display a marker indicating your location. Divers must check in and out at the park office.